Rotary cutter for edge-trimming machines.



No. 673,318. Pmhmu Apr. 30, 1901.

s. u. cormuzu.

ROTARY CUTTER FOR EDGE TRIMMING MACHINES.

(Application filed Aug. '22, 1900.)

(No Model.)

WITNESSES UNITED STATES PATENT OFFICE.

SAMUEL N. OORTHELL, OF QUINCY, MASSACHUSETTS, ASSIGNOR TO JAMES N.DARRAH, OF NEW YORK, N. Y.

ROTARY CUTTER FOR EDGE TRIMMING MACHINES.

SPECIFICATION forming part of Letters Patent No. 678,318, dated April30, 1901. Application filed August 22, 1900. Serial No. 27,724. (Nomodel.)

To all whom it may concern:

Be it known that I, SAMUEL N. GoRTIIELL, a citizen of the United States,residing at Quincy, in the county of Norfolk and State of Massachusetts,have invented a new and useful Improvement in Rotary Cutters forTrimming the Sole Edges of Boots and Shoes, of which the following is aspecification.

My invention relates to rotary cutters for trimming the sole edges ofboots and shoes; and it consists in a cutter having a series ofcutting-blades arranged around a central hub and every other blade inthe series being so constructed that the faces thereof which I 5 meetand form the cutting edges shall meet at a greater or less angle to eachother than that at which the like faces of the remaining blades meet,thus forming alternate cutting edges of different degrees of sharpnessin the same circle of revolution, as will be more fully explained.

Figure 1 represents a side view of a cutter embodying my invention. Fig.2 is an edge view of the same. Fig. 3 represents a modi- 2 5 fication bywhich the same result is obtained.

A represents the body of the cutter,on which are formed the series ofinclined blades b.

a represents the cutting edges of the blades, and c the tops of the sameinclined to the peripheral circle, every other top being given a greaterclearance or forming a greater angle with said circle and a smallerangle with the face I) of the blade, and consequently having a sharpercutting edge than the other blades have. I have found by long practicalexperience with this class of cutters that this novel constructionpossesses great advantages over any other kind of rotary cutter inpublic use. A keen cutting edge is desirable,

because it shaves the leather instead of boating it 01f, as dull edgesdo, and consequently does not compact and harden the edge by thehammering of the cutter-blades, but leaves it in better condition forthe finishing process,

known as setting or burnishing, If, however, the blades are all alikesharp, they will take too rank a hold of the edge and render itimpracticable to hold a shoe steadily up to them. To avoid thisdifficulty, sometimes blades without clearance or cutting 56 edges havebeen placed between sharp blades to act as guards or gages; but theresult of such a construction and arrangement is to produce a rough,uneven, and wavy edge, and such cutters are liable when run at the usual5 5 high speed to burn the stock by frictional heat; but cuttersconstructed as herein shown and described, having the cutting edges ofthe blades alternately thin and thick, whereby the less sharp blades actas cutting- 60 guards and prevent too rank a hold of the sharper blades,render it perfectly feasible to hold a shoe edge steadily up to them tobe trimmed, and the duller edges while so acting as a guard or gage tothe sharper blades also trim' lightly and brush over the edge withoutcompacting and hardening the same, thus leaving the sole edge in bettercondition for the blacking, burnishing, and final processes offinishing.

In Fig. 3 a modification is shown wherein the tops 0 of all the bladeshave the same clearance and form the same angle to the peripheral circlebut the fronts b are every other one under cut to a greater degree thanthe remaining blades, thus forming a smaller angle with top 0 andproducing alternate thick and thin cutting edges a.

I claim A rotary cutter for trimming the sole edges of boots and shoes,having a series of cuttingblades formed upon or arranged around a commonhub, and so constructed that the faces 17, and c, of the cutting-blades,which meet and form the cutting edges a, shall in every othercutting-blade, meet at a greater or less angle to each other than thatat which the like faces of the remaining cutting-blades meet;substantially as and for the purposes specified.

SAMUEL N. CORTHELL.

Witnesses:

EUGENE HUMPHREY, W. R. OGLESBY.

